© Safety and Installation Guide – Edition Dec. 2010 Scheuten Solar USA, Inc.
All rights reserved. Specifications in this manual are subject to change without notice.
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When connecting modules in parallel, each module (or series string of
modules so connected) shall be connected according to the maximum
series fuse as specified. Applicable regulations should be observed to
assure safety and maintain the warranty when working with electrical
devices. A maximum system voltage of 600 V must not be exceeded,
not even at especially low temperatures.
Depending on its set-up location and environmental conditions, a PV
module may supply higher voltages and / or higher current when
compared to standard testing conditions. For this reason, in order to
define the rated voltage values of components, rated current values of
wires, the size of fuses and the design of control systems that are to be
connected at the output of PV modules, the Isc and Voc values listed
on the module and in the data sheet may need to be adjusted. Refer to
Section 690-8 of the National Electrical Code for an additional
multiplying factor of 125% (80% derating) which may be applicable.
Depending on the installation location, special protection may need to
be taken against lightning and electrical surge. Tight parallel wiring of
the positive and negative conductors can reduce coupling of
interference currents.
3.4 Grounding
For safety reasons, ground the module frame or array before wiring the
circuit in a manner that is in accordance with NEC requirements for
grounding solar electrical systems. When grounding, use material that
is certified according to UL 1703. In addition, grounding hardware must
be compatible with other materials to avoid corrosion due to the use of
dissimilar metals. Grounding should only be performed by a qualified
electrician. Wiring shall be in accordance with the NEC and grounding
method shall also be in accordance with the NEC, article 250 and any
relevant local code and/or ordinance. Grounding method of the frame
of arrays shall comply with NEC, article 250.
Figure 3
– Designated Grounding Holes
It is critical that the grounding system be designed so that maintenance
and/or repair work of one module in the circuit will not interrupt the
grounding of any of the other modules. Each module has two
designated 0.17” grounding holes in the frame, shown in
Figure 3
, for
use with appropriate grounding hardware (not provided).
Table 2:
Recommended Grounding Components
Component
Description
Manufacturer/
Distributor
Part Number
Grounding Lug
Lay-In Lug
Ilsco
GBL-4DBT
Bolt
#6-32, SS
McMaster-Carr
92314A148
Serrated Washer
M5, SS
McMaster-Carr
91120A140
Washer
ID 9/64”, OD 3/8”, SS
McMaster-Carr
92141A007
Nut
#6-32, SS
McMaster-Carr
91841A007
See: www.ilsco.com; www.mcmaster.com
Scheuten Solar recommends using a UL listed lay-in ground lug such
as IIsco GBL-4DBT or equivalent, and stainless steel hardware (bolt,
washer, serrated washer and nut). A tooth washer (serrated washer)
should be used between the grounding lug and the module frame
because it is critical that the grounding hardware break through the
anodizing layer and establish electrical connection with the aluminum
frame. Grounding hardware for outdoor use should be stainless steel.
See
Table 2
for a list of recommended components. The assembly
must be torqued between 15 in-lbs to 20 in-lbs for #6-32 bolt.
Scheuten Solar recommends that the ground lug be secured using a
bolt, washer, serrated washer and nut assembly. The assembly shall
incorporate some type of locking mechanism (lock washer, lock nut
etc.) to maintain tension between the bolt and the assembly. The
grounding assembly should be designed to prevent components from
wiggling loose, which can jeopardize the integrity of the grounding
system. See Figure 4 below for an example of acceptable means of
equipment grounding. Refer to NEC article 690 on grounding PV
arrays for specific requirements.
Figure 4
– Grounding Example Drawings
1
.-
Nut
4
.-
Washer
2
.-
Serrated Washer
5
.-
Bolt
3
.-
Ground Lug
The equipment grounding conductor must not be smaller than No.14
AWG (2.1 mm
2
), must be sized according to the NEC and shall be of
copper, copper alloy, or other material acceptable for use as an
electrical conductor. Only the stainless steel set screw of the lay-in
ground lug provided by the supplier of the grounding material should
be used to securely attach the copper equipment grounding conductor.
Any UL approved PV grounding method and components are also
acceptable for the US and Canada.
4. Maintenance
Generally speaking, solar modules are maintenance free. For smaller
inclination angles, it may be necessary to clean the modules with
plenty of clean water. Avoid any harsh additives. When cleaning the
glass, typical cleaning tools may be used. Any dried dirt residue should
not be scratched or scraped off using sharp tools. Otherwise,
scratches or tears may cause damage to the glass surface. Every once
in a while, the modules should be inspected to assure they are in
proper condition, correctly wired and mounted. While doing so, assure
that they are still firmly attached and that there is no corrosion.
5. Liability
For liability see the Scheuten Solar website: www.scheutensolar.com
Revisions relating to technical improvements and enhancements
reserved